The present invention relates to inductive sealing units, and, specifically, to an inductive sealing unit that accommodates different size objects to be sealed.
Inductive sealing units are used to secure metal foil seals to the cap of a container. The metal foil seals generally have sealing material, such as a thermoplastic resin, disposed on one side. The caps with the metal foil seals are seated over the openings of the containers to be sealed. The side of the metal foil soil with the sealing material generally contacts the container so that the metal foil covers the opening of the container. The container, metal foil seal, and cap are passed through an electromagnetic field generated by applying a high frequency current to a conductive coil of the inductive sealing unit. The electromagnetic field inductively heats the metal foil seal, which in turn heats and cures the sealing material to secure the metal foil seal to the container; thereby sealing, hermetically sealing, or tamper-proof sealing the container. Generally, the metal foil seal must come in close proximity to the source of the electromagnetic field to ensure heat sufficient to seal the container is generated in the metal foil.
Conventional inductive sealing units are typically designed for caps with specific dimensions. In recent years, caps of containers have taken many shapes and sizes and it is not uncommon for a manufacturer to seal containers with an assortment of cap configurations. Caps of different sizes and shapes require manufacturers to use different inductive sealing units to ensure that the metal foil is in close proximity to the electromagnetic field. As a result, each time a manufacture wishes to seal a container that has a cap of with different dimensions, the manufacturer must generally stop the assembly line and replace the inductive sealing unit with another inductive sealing unit that is suitable for the sealing the container. Thus, manufactures are generally required to have a multitude of inductive sealing units for sealing containers having caps with different dimensions.
These conventional sealing units are burdensome to manufacturers that seal containers with different size caps. Requiring a manufacturer to stop the assembly line and replace the sealing unit with another sealing unit results in tremendous inefficiencies. These inefficiencies can increase the production times for sealing containers and increase the cost associated with manufacture of sealed containers with different size caps.
What is desired is an inductive sealing unit that can accommodate different size objects to be sealed.